Bollard

ABSTRACT

A bollard device (1) comprising an outer bollard member (2) and an inner bollard member (3) which is provided to be displaceable between a retracted position wherein the inner bollard member (3) substantially extends within an interior space (4) of the outer bollard member (2), and an extended position wherein part of the inner bollard member (3) extends above the outer bollard member (2) wherein the inner bollard member (3) comprises an upper part (5) and a lower part (6), wherein in the extended position the upper part (5) substantially extends above the outer bollard member (2) and the lower part (6) substantially extends within the interior space (4), wherein the lower part (6) of the inner bollard member (3) comprises at least two reinforcement elements (10a, 10b) wherein these reinforcement elements (10a, 10b) form protrusions of the inner bollard member (3).

This application is a national stage application of International Patent Application No. PCT/IB2018/060016, filed Dec. 13, 2018. The entirety of the aforementioned applications is incorporated herein by reference.

FIELD

The present invention relates to a bollard device comprising an outer bollard member which is provided to be anchored into the ground and a longitudinal inner bollard member which is provided to be displaceable according to an upright direction between a retracted position wherein the inner bollard member substantially extends within an interior space of the outer bollard member, and an extended position wherein an upper part of the inner bollard member extends above the outer bollard member and forms an obstacle for preventing the passage of a vehicle, wherein in the extended position the upper part substantially extends above the outer bollard member and a lower part of the inner bollard member substantially extends within the interior space of the outer bollard member.

BACKGROUND

This present invention specifically relates to such bollard devices wherein the upper part and the lower part together enclose a cavity which is accessible from the bottom of the inner bollard member and wherein the bollard device comprises displacing means for displacing the inner bollard member, wherein at least one of the said displacing means is substantially located inside the said cavity in the retracted position.

Such bollard devices are for example traffic bollard devices which are used to prevent the passage of a vehicle, while cyclist, pedestrians, wheelchairs etc. can still pass the bollard device. Such bollard devices are often used for temporarily closing off a road or a passage. For example these bollard devices can be used to close of shopping streets, streets in the vicinity of schools, streets in city centers, entrances of companies, entrances of military facilities, etc. for vehicles and this only when it is desired. Because the inner bollard member is displaceable between an extended position wherein the inner bollard member forms an obstacle and a retracted position wherein the entire bollard device is substantially located underground, one can easily regulate the passage of vehicles. For example, if a shopping street comprises several such bollard devices, one can close off the road for vehicles by placing the inner bollard members of these bollard devices in their extended position. If suddenly a priority vehicle needs to pass, one can easily put the inner bollard members in their retracted positions, such that the priority vehicle can pass. To prevent the passage of a vehicle, often more than one bollard device is used. The bollard devices can for example be placed at such a distance from each other, that the inner bollard members extend at approximately 90 cm from each other.

If the bollard device is used to close off a road, the outer bollard member is preferably anchored in the ground at the location of the road in such a way that, in the retracted position, the bollard device does not form a protrusion of the upper surface of the road. To displace the inner bollard member, the bollard device normally comprises a motor. In the past this motor was always located at a distance from the outer bollard member and below the road, meaning that big ditches needed to be dug out to install the bollard device and lots of concrete was needed to fill up these ditches. The structure of the inner bollard member is such that it can withstand impact forces. Nowadays there are also bollard devices of which the displacing means for displacing the inner bollard member, such as for example the motor, are at least partly located inside the inner bollard member in the retracted position. These bollard devices have less volume and thus require less space to install them, such that less concrete is needed and there is no need to dig out large ditches. If the motor is located inside the cavity, it is difficult to provide strengthening means inside said cavity to provide strength and rigidity to the inner bollard member. Therefore inner bollard members having a certain thickness are provided, such that the inner bollard member is capable to withstand impact forces. Such an inner bollard member therefore contains a relatively large amount of material.

It is therefore an object of the invention to provide a bollard device which is capable of withstanding impact forces, wherein a limited amount of material is needed to provide a sufficiently strong bollard device and wherein preferably this bollard device does not take up much volume.

The object of the invention is achieved by providing a bollard device as described in the first paragraph of this description wherein the lower part of the inner bollard member comprises at least two reinforcement elements which are located at a distance from each other with regard to the longitudinal direction of the inner bollard member, wherein these reinforcement elements form protrusions of the inner bollard member which are directed outwards and form partly the outer surface of said inner bollard member.

These reinforcement elements here form local thickenings of the inner bollard member. These thickenings locally strengthen the inner bollard member, such that it is not necessary that the entire inner bollard member has a certain thickness over its entire length and one can thus provide in an inner bollard member comprising a cavity, which still has the required strength but which comprises less material with regard to existing inner bollard members. Because there are two reinforcement elements which lie at a distance from each other according to the longitudinal direction, forces can be passed on to the outer bollard member at two different heights such that the bollard device can withstand great impacts. Preferably these reinforcement elements are arranged in such a way and/or have such a shape that when a vehicle crashes onto the upper part of the inner bollard member, both said reinforcement elements will come into contact with the outer bollard member, such that forces can be easily passed on to the outer bollard member. The reinforcement elements are directed outwards, such that they do not form obstacles which are directed inwardly and one can provide in a cavity in which displacement means can be located, such that a bollard device which takes up less volume can be provided. Here one does not have to excavate a large ditch to install the bollard device and for example less concrete is needed to anchor this bollard device into the ground. With the aid of said reinforcement elements which form outside protrusions, the displacement of the inner bollard member with regard to the outside bollard member is also easier because the possible contact surface between the inner bollard member and the outside bollard member can here be made smaller, such that the possible friction between the inner bollard member and the outside bollard member is less during the displacement of the inner bollard member. A said reinforcement element can also be used to prevent the displacement of the inner bollard member beyond a certain point, since they form a protrusion and one can provide in a retaining element along which the reinforcement element cannot pass. Because the reinforcement elements are located at a distance from each other according to the longitudinal direction, they will also help to keep the inner bollard member in an upright position during the use of the bollard device and the forces can be well absorbed over said distance.

Preferably the inner bollard member comprises a base element with an inner surface which surrounds a cavity and an outer surface which is located opposite the inner surface, wherein the reinforcement elements are connected to the base element at the height of the outer surface, such that the reinforcement elements form protrusions. Preferably this base element has a tubular shape, wherein the base element is only accessible from the bottom. The interior space of the outer bollard member then preferably has a cylindrical shape and the reinforcement elements then preferably are ring shaped with an outer diameter that corresponds to the diameter of the interior space. The base element can also have a rectangular shape, wherein the interior space of the outer bollard member then also preferably has a rectangular shape and the reinforcement elements then preferably have an outer circumference that corresponds to the corresponding dimensions of the interior space.

Preferably in use of the bollard device, the longitudinal direction corresponds to the upright direction. Also preferably the upright direction is substantially the vertical direction.

In a very preferred embodiment the upper part and the lower part together enclose a cavity which is accessible from the bottom of the inner bollard member and the bollard device comprises displacing means for displacing the inner bollard member, wherein at least one of the said displacing means is substantially located inside the said cavity in the retracted position. Here one can provide in a bollard device which takes up a relatively small amount of volume in the retracted position of the inner bollard member, but can still withstand relatively great impact forces.

Preferably, in the extended position, at the height of each said reinforcement element and according to a plane perpendicular to the upright direction, at least one outer dimension of the inner bollard member corresponds to the corresponding dimension of the interior space of the outer bollard member. Because at least one outer dimension of the inner bollard member corresponds to the corresponding dimension of the interior space of the outer bollard member, the inner bollard member substantially lies, at the height of at least two opposite points, against the outer bollard member at the height of a said reinforcement element, such that forces acting upon the upper part of the inner bollard member can be well passed on to the outer bollard member and can thus well be absorbed. Here the inner bollard member will also be more likely to stay upright, when a vehicle crashes into the upper part of the inner bollard member. Here, the reinforcement elements will also help to guide the inner bollard member during its displacement.

In a preferred embodiment a said reinforcement element, according to a plane perpendicular to the longitudinal direction of the inner bollard member and at the height of said reinforcement element, forms substantially the whole circumference of the inner bollard member. Here the inner bollard member can pass on forces onto the outer bollard member over its whole circumference such that impact forces with different directions acting upon the bollard device can be well withstood. More preferably, in the extended position, at the height of both the said reinforcement elements and according to a plane perpendicular to the upright direction, the outer circumference of the inner bollard member corresponds to the dimensions of the interior space of the outer bollard member. Here each reinforcement element substantially lies against the outer bollard member over its entire circumference such that with the aid of said reinforcement elements, forces can be well passed on to the outer bollard member. These reinforcement elements also help the displacement of the inner bollard member according to the upright direction.

Preferably the outer bollard member comprises a shaft, which forms the said interior space of the outer bollard member in which the inner bollard member is displaceable, wherein the cross section of the shaft over substantially its entire length is similar and in which the outer dimensions of the circumference of the inner bollard member at the height of the reinforcement elements, corresponds to the dimensions of said cross section of the shaft. In this way the reinforcement elements and the shaft help the keep the inner bollard member in a desired position during the displacement of the inner bollard member and this over the entire displacement between the retracted position and the extended position and vice versa. Here the shaft and the inner bollard member ensure in an easy manner, that the inner bollard member is always displaced according to an upright direction and this with little friction.

Preferably, if the bollard device comprises a said cavity, the inner bollard member has a longitudinal base element which forms the said cavity, wherein the reinforcement elements lie against the outside of said base element. Said base element then preferably forms substantially the upper part of the inner bollard member and forms partly the lower part since this lower part also comprises among others the reinforcement elements. This base element can for example be a tube. The reinforcement elements can for example be welded to the base element if both the reinforcement element and the base element are made out of steel.

Further preferably the bollard device comprises a cover to partially cover up the top of the shaft, wherein this cover extends partly into the shaft and comprises an opening with a cross section which corresponds to the cross section of the longitudinal base element such that during the displacement of the inner bollard member from the retracted position to the extended position, the longitudinal base element will pass trough said opening until a said reinforcement element contacts the cover, wherein preferably this cover comprises a steel part. The cover, when it has a steel part, has a certain strength. Preferably this steel part extends into the shaft. When the reinforcement element contacts the cover, the bollard device is in its fully extended position. The cover prevents the movement of the inner bollard member out of the outer bollard member. The cover thus forms a said retaining element. Because of the strength of the cover, the displacement to the extended position can happen smoothly. Since the cover extends partly into the shaft the cover will also help to withstand impact forces, since forces can be well passed along from the first reinforcement element to the cover and to the outer bollard member.

In a preferred embodiment the inner bollard member comprises at least one upright extending bar element which is preferably located between the said at least two reinforcement elements according to the longitudinal direction, wherein this bar element also forms a protrusion of the outer surface of the inner bollard member which is directed outwards. This bar element strengthens the inner bollard member such that forces can be better withstood. This bar element also ensures that the inner bollard member is less likely to break at the height were the bar element is located. If the bar element is located between the reinforcement elements this means that relatively great impact forces upon the upper part can be withstood. This bar element here forms a local thickening. Because of this local thickening it is not necessary that the inner bollard member has a certain thickness over its entire length such that the inner bollard member can be made much thinner at other places in comparison with already existing inner bollard member which are able to withstand the same impact forces and the inner bollard member according to this preferred embodiment can be made with even less material. Preferably the inner bollard member comprises two are more said bar elements. These bar elements can be connected to the reinforcement elements such that forces can be well passed on between the reinforcement elements and then to the outer bollard member.

The inner bollard member comprises preferably at least one upright extending sliding bar, wherein this sliding bar forms a protrusion of the outer surface of the inner bollard member which is directed outwards, for facilitating the displacement of the inner bollard member. This sliding bar here helps to facilitate the displacement of the inner bollard member from the retracted position to the extended position and vice versa. With the aid of a said sliding bar more contact surface between the inner bollard member and the outside bollard member can be easily created such that the guiding of the inner bollard member in the interior space is enhanced and this without the need of relatively much material and thus without increasing the friction significantly. More preferably this sliding bar is situated between two said reinforcement elements. This sliding bar can be made out of a synthetic material and can have a certain smoothness such that it can glide without causing much friction.

In a preferred embodiment, wherein the inner bollard member comprises a said cavity, the displacement means comprise a motor, wherein this motor is located inside the said cavity in the retracted position and in the extended position. Here the motor is protected by the inner bollard member in all positions of the inner bollard member. Preferably, in the extended position, the motor is located at the height of the reinforcement elements, and even more preferably substantially between the two reinforcement elements, such that the risk is low that the motor gets damaged during the impact of a vehicle onto the upper part of the inner bollard member.

In a very preferred embodiment the bollard device comprises a stationary pillar which is situated within the interior space of the outer bollard member, wherein at least some of the said displacement means are connected to the pillar. By connecting the displacement means to a pillar, they can be well kept in place. The pillar, with the at least some of the said displacement means, can be in a simple manner placed inside and lifted out of the interior space as a whole, making it easy to install the bollard device and making it also easy to repair/change the said displacement means. When there is a said cavity, which is accessible from the bottom, said cavity can be made as such that the inner bollard member can slide along the pillar. Preferably then, the pillar rests upon a bottom which surrounds the interior space and is situated centrally inside said interior space. Here is also easy to connect the inner bollard member with the displacement means.

Further preferably the pillar extends according to the upright direction and the displacement means comprise a chain and a sprocket, wherein this chain and this sprocket are connected to the pillar. With the aid of such a chain and sprocket, the inner bollard member can be easily displaced according to the upright direction. The inner bollard member can for example be connected and/or rest upon a support plate which is connected to the said chain and thus undergoes the displacement of the chain. In an alternative embodiment the displacement means can comprise a rack and pinion.

Also further preferably, if the displacement means comprises the said motor, the motor rests upon the pillar. Here the motor can be placed in a relatively high position such that the risk is lower that it gets damaged by water. The displacement of the inner bollard member from the extended position to the retracted position will in certain embodiments of the bollard device create an air displacement which is sufficient to move the water to the bottom of the interior space. If at the height of this bottom there are passages to the outside surrounding the bollard device, the water will be pushed outside the interior space such that the risk is low that the motor will be damaged by water.

In a preferred embodiment the lower part of the inner bollard member is connected to the displacement means, such that the inner bollard member is displaceable. This connection is preferably located near the bottom of the lower part. Further preferably, if the displacement means comprises a said motor, the motor is substantially located above the said connection in all positions of the inner bollard member.

In a very preferred embodiment the outer bollard member comprises at least two strengthening elements, which are located at a distance from each other with regard to the upright direction, wherein these strengthening elements form protrusions of the outer bollard member which are directed outwards and form partly the outer surface of said outer bollard member, and wherein, in the extended position, at least one strengthening element is located at the height of a respective reinforcement element. With the aid of said strengthening elements the outer bollard member can be provided much thinner at other locations, such that the amount of material needed to create a sufficiently strong outer bollard member which can withstand impact forces, is less then with similar existing outer bollard members. Also because at least one said reinforcement element is located at the height of a said strengthening element in the extended position, this bollard device can withstand great impact forces. This because this reinforcement element will pass on forces to the outer bollard at the height of the said strengthening element. Preferably all the strengthening elements are located at the height of a respective reinforcement element in the extended position of the inner bollard member.

Further preferably the outer bollard member comprises at least one upright extending support element which preferably connects the said at least two strengthening elements, wherein this support element also forms a protrusion of the outer surface of the outer bollard member which is directed outwards. This support element connects the two strengthening elements such that forces can be even better passed on between the strengthening elements and thus better absorbed. This support element also ensures that the outer bollard member is less likely to break at a point located between the strengthening elements, such that this support element provides the outer bollard member with more strength. This support element here forms a local thickening. Because of this local thickening it is not necessary that the outer bollard member has a certain thickness over its entire length such that outer bollard member can be made much thinner at other places in comparison with already existing outer bollard members which are able to withstand the same impact forces and thus the outer bollard member according to this embodiment can be made with even less material. Preferably the outer bollard member comprises two are more said support elements.

In a specific embodiment the outer bollard member comprises a passage which connects the interior space with the outside which surrounds the outer bollard member, such that water can flow from the interior space to the outside. This is of importance if water gets inside the interior space, since it is not favourable that the lower part of the inner bollard member and the displacement means come into contact with water. The displacement of the inner bollard member from the extended position to the retracted position will in certain embodiments of the bollard device create an air displacement which is sufficient to move the water such that the water is then pushed trough said passage.

In a very preferred embodiment the inner bollard member substantially has a tubular shaped base element which forms the said cavity, wherein the reinforcement elements extend next to the base element according to the longitudinal direction. The reinforcement elements can be connected to the base element. This could be the case if the reinforcement elements are made of a different material then the base element. The reinforcement element can also directly merge into the base element. This is preferably the case if the reinforcement elements are made out of the same material as the base element and the reinforcement elements and the base element are made together as one whole. If a said bar element is present, it can be made out of the same material as the reinforcement elements and it can be made as one whole together with the reinforcement elements and/or the base element.

The present invention is now explained in greater detail below with reference to the following detailed description of some preferred embodiments of a bollard according to the present invention. The aim of this description is solely to give illustrative examples and indicate further advantages and particularities and thus cannot be interpreted as a limitation of the field of application of the invention or of the patent rights claimed in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

In this detailed description, reference is made by means of reference numerals to the appended drawings, wherein

FIG. 1 shows a cross section of a bollard device according to the invention, wherein the inner bollard member is in the retracted position;

FIG. 2 shows a cross section of the bollard device shown in FIG. 1, wherein the inner bollard member is in the extended position;

FIG. 3 shows a front view of the bollard device as shown in FIG. 1, wherein the inner bollard member is in the retracted position;

FIG. 4 shows a perspective view of the bollard device as shown in FIG. 1, wherein the inner bollard member is in the retracted position;

FIG. 5 shows a front view of the bollard device as shown in FIG. 1, wherein the inner bollard member is in the extended position;

FIG. 6 shows an exploded view of the bollard device as shown in FIG. 1;

FIG. 7 shows a perspective view of the inner bollard member of the bollard device shown in FIG. 1;

FIG. 8 shows a perspective view of the pillar and some displacement means of the bollard device shown in FIG. 1.

DETAILED DESCRIPTION

In the figures one embodiment of a bollard device (1) according to the invention is shown. The bollard device (1) comprises an inner bollard member (3), an outer bollard member (2), displacement means, a pillar (13), a cover plate (20) and a cover ring (21). This cover ring (21) comprises a lower part, namely a ring shaped element, which is made out of steel, such that the cover ring (21) is sufficiently strong.

The longitudinal outer bollard member (2) is provided to extend vertical in use. This outer bollard member (2) is among others clearly visible in FIGS. 2, 3 and 6. The outer bollard member (2) comprises a tubular main element (25) which extends according to the longitudinal direction of the outer bollard member (2), two annular shaped strengthening elements (15 a, 15 b) which lie around and against the outside of the main element (25) and are welded to the main element (25) in such a way that they both extend around the entire circumference of the main element (25) according to a plane perpendicular to said longitudinal direction. These two strengthening elements (15 a, 15 b) are located at a distance from each other according to said longitudinal direction and a first said strengthening element (15 a) is located at the height of the top of the outer bollard member (2) an a second said strengthening element (15 b) is located below said first strengthening element (15 a). The outer bollard member (2) further comprises several bar shaped support elements (16) which lie against the main element (25) and are welded to the main element (25), wherein the support elements (16) extend according to the longitudinal direction, extend between the strengthening elements (15 a, 15 b) and are in contact with both strengthening elements (15 a, 15 b). The outer bollard member (2) further comprises two beams (19) which are connected to the main element (25) just below the first strengthening member (15 a) and which are provided to extend in a horizontal direction, and a holder (24) for electrical components such as control elements for controlling the movement of the inner bollard member (3). The main element (25) encloses, together with a base plate (22) of the outer bollard member (2) which is connected to the bottom of the main element (25), a cylindrical shaped interior space (4). The main element (25) comprises passages (17) just above the base plate (22) which connect the interior space (4) with the outside. With the aid of the base plate (22) the outer bollard member (2) can be placed upon the bottom of an excavated ditch and the outer bollard member (2) further comprises leveling means (23) to level the main element (25) such that it extends according to a vertical direction. Here the cover plate (20) and the cover ring (21) are seen as separate parts of the bollard device (1), but they can also be seen as part of the outer bollard member (2). The outer bollard member (2) is anchored into the ground in such a way that the cover plate (20) and cover ring (21) lie in the plane of the road surface.

The inner bollard member (3), which is clearly visible in FIGS. 1, 2 and 7, comprises a tubular base element (18) with two openings at its ends which give access to the cavity (7) that it surrounded by the tubular base element (18). The opening at the top is closed off by a disk. In FIG. 7 this disk is not shown. The cavity (7) is therefore only accessible from the bottom. The inner bollard member (3) further comprises two reinforcement elements (10 a, 10 b), bar elements (11) and sliding bars (12). The inner bollard member (3) comprises an upper part (5) and a lower part (6), wherein in the extended position the upper part (5) substantially extends above the outer bollard member (2) and the lower part (6) substantially extends within the interior space (4) of the outer bollard member (2). The upper part (5) is only formed by the base element (18) and the said disk. At the height of the upper part (5), the base element (18) can be coated such that the upper part (5) of the inner bollard member (3), which is visible in the extended position, is esthetically pleasing. The lower part (6) comprises part of the base element (18) and the reinforcement elements (10 a, 10 b), bar elements (11) and sliding bars (12), which are connected to said part of the base element (18). The reinforcement elements (10 a, 10 b) are rings which surround the base element (18) and are welded to the base element (18). They extend at a distance from each other according to the longitudinal direction of the base element (18). In the extended position a first said reinforcement element (10 a) extends just below the road surface. The bar elements (11) lie between the reinforcement elements (10 a, 10 b), extend upright, are welded to the base element (18) and lie against both reinforcement elements (10 a, 10 b). The sliding bars (12) extend upright, lie between the reinforcement elements (10 a, 10 b) and are connected with bolts and nuts to the base element (18). The section (14) of the lower part (6) that lies beneath a said second reinforcement element (10 b) is connected to and rests upon a support plate (9) of the displacement means (see further). The outer diameter of the reinforcement elements (10 a, 10 b) substantially corresponds to the inner diameter of the main element (25) such that the inner bollard member (3) is guidingly movable according to the vertical direction between its retracted position and its extended position and vice versa.

The bollard device (1) also comprises a pillar (13) and displacement means to displace the inner bollard member (3) from its retracted position to its extended position and vice versa. The pillar (13) rests upon the base plate (22) of the outer bollard member (2), extends upright and is located centrally in the interior space (4). The displacement means comprise among other, a motor (8), a chain (not shown) which is displaceable by said motor (8), the support plate (9) upon which the said section (14) of the lower part (6) of the inner bollard member (3) rests and to which the said lower part (6) is connected, and wherein said support plate (9) is connected to the chain and follows the movement of the chain, control means which control the motor (8). These control means are situated in the holder (24) and are connected to the motor (8). These control means can for example control the motor (8) in such a way that the position of the inner bollard member (3) depends upon the day, the hour, etc. The cover plate (20) closes of the holder (24) such that the control means are still accessible once the bollard device (1) is installed in place. These control means can for example be operated wireless, such that for example when a priority vehicle needs to pass, one can quickly place the inner bollard member (3) in its desired position.

The inner bollard member (3) is arranged movable in the interior space (4) of the outer bollard member (2) in such a way that the inner bollard member (3) is displaceable between its retracted position, wherein the inner bollard member (3) is substantially located inside the interior space (4) and the disk lies in the plane of the road surface, and its extended position wherein the upper part (5) of the inner bollard member (3) substantially is located above the road surface and forms an obstacle for vehicles. In the extended position, the reinforcement elements (10 a, 10 b) are located at the height of the respective strengthening elements (15 a, 15 b). The cover ring (21) surrounds an opening with a diameter that corresponds to the diameter of the base element (18) such that the upper part (5) of the inner bollard member (3) can pass trough said opening. The outer diameter of the first reinforcement element (10 a) is greater than the diameter op said opening, such that the cover ring (21) prevents the displacement of the lower part (6) of the inner bollard member (3) above the road surface and the lower part (6) is located in the interior space (4) in all the positions of the inner bollard member (3).

The installation of the bollard device (1) to close off a road can be as following. First a ditch is dug out, such that the outer bollard member (2) can be anchored in the ground in such a way that the cover plate (20) and cover ring (21) lie in the plane of the road surface. The outer bollard member (2) is placed on the bottom of the excavated ditch, which can for example be a concrete ground plate. With the aid of the leveling means (23) it is ensured that the main element (25) extends according to a vertical direction. To anchor the outer bollard member (2), concrete and reinforcement meshes are used. The reinforcement meshes are connected to the beams (19). With the aid of this beams (19), several bollard devices (1) can be connected to each other. Then the pillar (13), the displacement means and the inner bollard member (3) are placed inside the outer bollard member (2) and the section (14) of the inner bollard member (3) is connected to the support plate (9). The cover plate (20) is attached to the holder (24) and the cover ring (21) is attached to an attachment plane (26) of the outer bollard member (2) in such a way that the opening of the cover ring (21) surrounds the upper part (5) of the inner bollard member (3) at the height of the disk in the retracted position of the inner bollard member (3), such that the lower part (6) of the inner bollard member (3) cannot pass the cover ring (21).

The different elements of the bollard device (1), except for the sliding bars (12) and the displacements means (8, 9), are substantially made out of steel. The reinforcement elements (10 a, 10 b), the strengthening elements (15 a, 15 b) and the bar elements (11) are made out of a stronger steel then the main element (25) and the base element (18). The sliding bars (12) are made out of a synthetic material which is strong and suitable to guide the inner bollard member (3) during its displacement, such as polyoxymethylene. 

1. A bollard device (1) comprising an outer bollard member (2) which is provided to be anchored into the ground and a longitudinal inner bollard member (3) which is provided to be displaceable according to an upright direction between a retracted position wherein the inner bollard member (3) substantially extends within an interior space (4) of the outer bollard member (2), and an extended position wherein an upper part (5) of the inner bollard member (3) extends above the outer bollard member (2) and forms an obstacle for preventing the passage of a vehicle, wherein in the extended position the upper part (5) substantially extends above the outer bollard member (2) and a lower part (6) of the inner bollard member (3) substantially extends within the interior space (4) of the outer bollard member (2), wherein the lower part (6) of the inner bollard member (3) comprises at least two reinforcement elements (10 a, 10 b) which are located at a distance from each other with regard to the longitudinal direction of the inner bollard member (3), wherein these reinforcement elements (10 a, 10 b) form protrusions of the inner bollard member (3) which are directed outwards and form partly the outer surface of said inner bollard member (3).
 2. The bollard device (1) according to claim 1, wherein the upper part (5) and the lower part (6) together enclose a cavity (7) which is accessible from the bottom of the inner bollard member (3) and wherein the bollard device (1) comprises displacing means (8, 9) for displacing the inner bollard member (3), wherein at least one of the said displacing means (8, 9) is substantially located inside the said cavity (7) in the retracted position.
 3. The bollard device (1) according to claim 1, wherein the extended position, at the height of each said reinforcement element (10 a, 10 b) and according to a plane perpendicular to the upright direction, at least one outer dimension of the inner bollard member (3) corresponds to the corresponding dimension of the interior space (4) of the outer bollard member (2).
 4. The bollard device (1) according to claim 1, wherein a said reinforcement element (10 a, 10 b), according to a plane perpendicular to the longitudinal direction of the inner bollard member (3) and at the height of said reinforcement element (10 a, 10 b), forms substantially the whole circumference of the inner bollard member (3).
 5. The bollard device (1) according to claim 1, wherein the outer bollard member (2) comprises a shaft, which forms the said interior space (4) of the outer bollard member (2), wherein the cross section of the shaft over substantially its entire length is similar and in which the outer dimensions of the circumference of the inner bollard member (3) at the height of the reinforcement elements (10 a, 10 b), corresponds to the dimensions of said cross section of the shaft.
 6. The bollard device (1) according to claim 2, wherein the inner bollard member (3) has a longitudinal base element (18) which forms the said cavity (7), wherein the reinforcement elements (10 a, 10 b) lie against the outside of said base element (18).
 7. The bollard device (1) according to claim 5, wherein the bollard device (1) comprises a cover (21) to partially cover up the top of the shaft wherein this cover (21) extends partly into the shaft and comprises an opening with a cross section which corresponds to the cross section of the longitudinal base element (18) such that during the displacement of the inner bollard member (3) from the retracted position to the extended position, the longitudinal base element (18) will pass trough said opening until a said reinforcement element (10 a) contacts the cover (21).
 8. The bollard device (1) according to claim 1, wherein the inner bollard member (3) comprises at least one upright extending bar element (11), wherein this bar element (11) also forms a protrusion of the outer surface of the inner bollard member (3) which is directed outwards and which is preferably located between the said at least two reinforcement elements (10 a, 10 b).
 9. The bollard device (1) according to claim 1, wherein the inner bollard member (3) comprises at least one upright extending sliding bar (12), wherein this sliding bar (12) forms a protrusion of the outer surface of the inner bollard member (3) which is directed outwards, for facilitating the displacement of the inner bollard member (3).
 10. The bollard device (1) according to claim 2, wherein the displacement means comprise a motor (8), wherein this motor (8) is located inside the said cavity (7) in the retracted position and in the extended position of the inner bollard member (3).
 11. The bollard device (1) according to according to claim 2, wherein the bollard device (1) comprises a stationary pillar (13) which is situated within the interior space (4) of the outer bollard member (2), wherein at least some the said displacement means are connected to said pillar (13).
 12. The bollard device (1) according to claim 11, wherein the pillar (13) extends according to the upright direction and the displacement means comprise among others a chain and a sprocket, wherein this chain and this sprocket are connected to the pillar (13).
 13. The bollard device (1) according to claim 10, and wherein the motor (8) rests upon the pillar (13).
 14. The bollard device (1) according to claim 1, wherein the lower part (6) of the inner bollard member (3) is connected to at least one of the displacement means, such that the inner bollard member (3) is displaceable.
 15. The bollard device (1) according to claim 1, wherein the outer bollard member (2) comprises at least two strengthening elements (15 a, 15 b), which are located at a distance from each other with regard to the upright direction, wherein these strengthening elements (15 a, 15 b) form protrusions of the outer bollard member (2) which are directed outwards and form partly the outer surface of said outer bollard member (2), and wherein, in the extended position, at least one strengthening element (15 a, 15 b) is located at the height of a respective reinforcement element (10 a, 10 b).
 16. The bollard device (1) according to claim 15, wherein the outer bollard member (2) comprises at least one upright extending support element (16) which connects the said at least two strengthening elements (15 a, 15 b), wherein this support element (16) also forms a protrusion of the outer surface of the outer bollard member (2) which is directed outwards.
 17. The bollard device (1) according to claim 1, the outer bollard member (2) comprises a passage (17) which connects the interior space (4) with the outside which surrounds the outer bollard member (2), such that water can flow from the interior space (4) to the outside.
 18. The bollard device (1) according to claim 1, wherein the interior space (4) has a cylindrical shape and the reinforcement elements (10 a, 10 b) have a circular circumference. 